If you can’t get into the messy stuff and get out, you’re missing a good amount of fish. I’ve always been a fan of casting into cover and finding the old cautious fish who hides from everything and has learned well the art of the ambush. I think of them like a skittish cat. They’ll play if you give them something worth playing with but it might take a bit of catnip and time.
When I throw to the fish in the heavy stuff I always do two things: Shorten the leader and step up the poundage. There’s not a thought given to leader shy fish here. These are ambush predators going after something struggling and they usually can’t see it. They feel it. Once you hookup with a fish you had best have some stout leader to get it out of the mess before you get all sorts of wrapped up in it and say good day to your fly and your fish.
Oh, and make sure your knots are strong. There are monsters lurking in the shadows.